


Nightmare Midnight

by Madlyinlov3onda



Series: Sans Nights [2]
Category: Undertale (Video Game)
Genre: F/M, M/M, Other
Language: English
Status: Completed
Published: 2017-11-19
Updated: 2017-11-19
Packaged: 2019-02-04 04:47:45
Rating: General Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 3,964
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12763497
Author URL: https://archiveofourown.org/users/Madlyinlov3onda/pseuds/Madlyinlov3onda
Summary: Sans Days after-fic, same as rules as Sans Nights but more Gaster-centric.I mostly wrote this because I had a nightmare and wanted Gaster to fix it.





	Nightmare Midnight

**Author's Note:**

> New Sans Days series….? Kinda??? I wanted to write some Gaster-centric fics that were still based in Sans Days, more into the future. Same rules as Sans Nights (Chapters are optionally-canon, reader’s gender will never be specified but genitalia might be mentioned with warnings if necessary, mostly just for smut or non-plot fun), tho added on I suppose Gaster is somewhat in a poly relationship with Reader and Sans. Well, not established in this chapter, but maybe future ones? Idk man, I just felt like writing the Gast-bro.
> 
> Main reason I wrote this is that I don’t do well with scary movies and nightmares, and writing this helped me get out of my jitteriness after both encounters lol. The nightmare is 100% an actual nightmare I had- and let me tell you it was The Worst. This chapter was basically self-therapy for me tbh.
> 
>  
> 
> Also this might be like the first writing I've posted that doesn't have a cliffhanger. Don't get me wrong, I originally had one, but I wanted closure for myself lmao. Enjoy!

 

 

“You cannot honestly still be thinking about that film.” Gaster’s voice caused you to jump slightly from the bed. You looked over, seeing him standing in the doorway to your room with a judgmental look on his face. “You barely watched ten minutes of it before giving into your fear and claiming you were too tired.”

“How- Whaaa? Nahh...” You tried to play it cool, pushing the blankets so they weren't as bunched close to your chest as you originally had them.

“The past twenty minutes I have been sitting on that couch utterly full of determination, which only happens during times of your adrenaline. I think we both know by this point the only thrill you get nowadays is by being terrified.” Gaster clarified with slight exaggeration and rolling his eye haloes. You quickly motioned your hand in a lazy wave and trying to play off the very true statement he just said.

“Pssh. Yeah right. That movie didn’t scare me. It's just... taxes. And things.” You could tell by his face that he wasn't convinced. “Bills. That sort of thing. Normal humans get stressed about that sort of thing.” You continued, seeing that he was even less convinced now. He sighed and walked over to your bed, sitting down next to you but keeping his eyes to the wall. 

“You are, by far, the worst liar I have ever met.” He muttered.

“If people knew you were a good liar, wouldn’t that mean you were a bad liar?” You asked, and you saw his eyebrow bone raise ever so slightly. Haha, point one for you. 

“Hmm. Valid point. However, I can literally feel how quickly your heart is beating, and I highly doubt ‘taxes and things’ are the cause of that.” He glanced down at you, and you felt static at your toes. “Forgive me for not being my brother in this situation, I am sure he would be much better at comforting you than I would be. Perhaps I could visit his work for you?” 

“Oh, no- of course not! He is on bad enough terms with his boss already… Really, I’m fine. You can go back to the movie, sorry I made you worried…” You sat up.

“Incorrect.” 

“Huh?” You asked, blinking at his objecting, and not sure what exactly you got wrong. 

“You did not make me worried, I was simply concerned about the excessive amounts of fear you were under.” He explained, and to you it sounded like what you just said but with more words. “Perhaps you would get better results for sleeping if you attempted it on the couch. I will put something else on the television for you.” Gaster stood and started walking towards the door. 

“What? No it’s okay, you don’t have to-” You quickly objected, pausing when he turned back to face you with glowing haloes. White, so he wasn’t using his magic, but it was still very ominous in the darkness of the room.  

“I know I do not have to do anything you request. However, you did not request this of me, correct?” He offered, slight tilt of his head. “Living room.” He finished, gracefully turning away and walking out of your sight. 

Your head spun at the confusing roundabout way Gaster seemed to care about you, and quickly slipped out of your bed and grabbed the blanket and pillow. When you got to the living room, Gaster was sitting on one side of the couch, the rest of it had been cleared. You paused, not exactly knowing how Gaster wanted you to sleep on the couch with him on it. He saw your hesitation and patted the armrest next to him. 

“Papyrus told me that humans calm down when their head is being rubbed, similar to dogs, is that correct?” He asked, and you had to hold back your laughter. 

“I mean…  I suppose? Last time Papyrus did it to me it really helped, but that was when Sans was… well...” You trailed off, not exactly sure if that was still a touchy subject. Gaster nodded anyway, repeating the patting motion to the armrest. 

“Then rest your head here, I shall try my best to comfort despite my inexperience.” His gaze went back to the tv, and you saw that he had just some human show on with the volume low as it possibly could without being muted, and the subtitles on. You felt a bit awkward about it but maybe he had a good idea. You placed the pillow on his lap and carefully crawled on, getting your head comfortable on the arm rest. 

You felt the blanket adjusted to be more even on you before Gaster’s holed hand rested on top of your head, startling you ever so slightly. Gaster let out a low chuckle. 

“Do not be so jumpy with me. The point of this is to calm you down.” Despite what he said, his voice still sounded slightly humored. You felt your cheeks heat up in embarrassment, thankful that you weren’t facing him. “Go ahead and rest. No aliens from other planets will be after you tonight. I shall fend them off for you.” 

You couldn’t help but to give a laugh at that. “Pft. Thanks Gaster... I really appreciate it.” You closed your eyes and took a deep breath, allowing yourself to take comfort in the slow motions Gaster’s hand made atop your head. After a little while he rested his other hand on your back, getting into a more comfortable position himself. 

The quiet background noise of the tv helped keep the images of the alien from the movie out of your head, and you felt your breathing slow, and darkness accept you.

.

_ It is just a game. _

_ It is just a game. _

_ It is just a game. _

You had to keep repeating that phrase to yourself as you ran in the office hallways, feeling the panic rising up inside of you. Even though you couldn’t remember how you ended up testing someone’s new Virtual Reality game they made. They didn’t tell you it was a horror game. 

They didn’t tell you how  _ realistic _ everything would seem. 

You could see the damp mold along all of the edges of the walls, the spiderwebs that caught the flickering fluorescent lights just right, the sound of something coming from the hallways behind you.  _ You hated it. _

Trying to keep whatever was behind you as far back as physically possible, you kept running until you met another hallway intersection. Three choices laid before you, none of them ones you would ever choose in any other circumstances. The one to your left was drenched in darkness, but the bright light further down that way allowed you to see a massive lump silhouette against one of the walls, like a cocoon of some sort. The middle choice had better but still dim lighting, but you could see where the tiles have been broken up and replaced with something lumpy and fleshy, and you could see it pulse and move. The rightmost choice was a hallway that had a flickering light, allowing you to make out scratches and cracks all along it’s floor and walls. 

This choice was a lot easier than some of the other hallways, at least. You gritted your teeth and ran through the right hallway, only to notice the bugs crawling out of cracks as you already started making your way down. You smacked your hands over your mouth to keep from screaming as you ran, trying to keep your eyes ahead of you. 

Another intersection, another choice. You could feel whatever what was following you though their heavy footsteps, that were steadily getting closer. You stopped considering all of the choices, and settled with just going with the first option that you saw that didn’t look  _ alive _ . 

Left. Right. Straight. Straight. Left. 

You refused to look behind you as you charged down the hallways, feeling as if the thing was just feet away from you at this point. But finally, after so many intersections, you noticed a doorway up ahead. You practically cried out of joy when you saw that, so happy to be over with this. You saw more options of doorways down the hall, but you went into the the first room you saw and reached for the door handle.

Only for your hand to grab empty air. 

“ _ Wrong choice. _ ” A voice that you couldn’t determine if it was masculine or feminine said almost happily, and the air in the empty room went cold. 

The heavy footsteps slowed down, and your breath caught in your throat as you gradually turned to face the monster for the first time. 

It was not any monster from the underground. 

It was Horror itself.

The entire being looked vaguely humanoid, however about three times as large and made of knotted grey flesh, composed of too many faces and not enough eyes. It was smiling without teeth in any of its mouths, and you could see movement under its skin stretch outwards, like something was trapped inside and reaching for you. It took another step forward, it’s thick feet stomping wetly to the ground at a relaxed, slow pace. It knew it won. 

You brought your hands to your mouth as you screamed and backed more into the empty room, watching in terror as the only exit of the room was the one the Horror was using as an entrance. 

“ _ I want out. Let me out. I’m done. Game over. _ **_Let me out._ ** ” You screamed, grabbing at your face and trying to get ahold of the headset, only to not feel anything except yourself. It wasn’t a game. It was too real to be a game. You cried out as you tried grabbing the headset again, knowing you wouldn’t be able to escape from the Horror. You were done for.

“ _ Calm down. _ ” A familiar voice uttered right next to you, and you felt a warm embrace from someone much taller than you. The next moment you felt the sensation of teleporting, and the two of you dropped an inch onto damp carpet. Warm hands grabbed the sides of your face and turned you to face their owner. 

“...  _ Gaster _ ?” You whispered, voice strained from your crying. It has been a while since you’ve seen him so serious. “What… What are you doing here? I-I-... I thought-” The floor shook under you, and you could feel the Horror running again, looking for you. 

“You are in a dream.” Gaster explained, keeping his hands firm to the sides of your face, making sure you didn’t look anywhere except for at him. The words sounded strange, echoing despite nothing else echoing in the hallway.  _ Dream… Dream… _

“A… dream?” You asked, and suddenly felt very aware of everything around you, more in the moment. Your eyes widened, realizing what he said was true. “Wake me _up_ , Gaster, _please_. I don’t want to be _here_ _anymore_.” You started sobbing again. Gaster embraced you.

“Shh shh shh…” Gaster’s soft shushing caught you off guard, and you could feel his arms tighten around you, one hand behind your head and keeping you close. “The fact you didn’t immediately wake up at that… means we have to be clever.” 

“Just wake me up, _ please,  _ **_Gaster_ ** _. _ ” Your voice strained harder as you felt broken, wanting nothing more than to be rid of the terrible nightmare. He replied with more gentle shushing, slowly releasing you from his tight embrace. The stomping was getting closer. 

“Listen to me carefully.” Gaster knelt down to eye level for you- something he has never done before. “I cannot wake you up. We need to finish the dream.” You felt more tears build up at his words, but he brought his hand up and brushed them away with his thumb, ignoring the growing stomps. “It will only come back to haunt you later if we do not finish this now. We need to defeat the nightmare.” He said slowly and clearly, and every time you tried to see past him he would gently bring your attention to him. 

“We  **_can’t_ ** . Did you see that thing? Its…. its…” You tried explaining, but Gaster only smiled. 

“Just a dream.” He finished the sentence for you, slowly standing up and turning to face the hallway. He kept one hand behind him as if to keep you back, and waited. 

A silent moment passed. Then another. 

Part of the hallway exploded into bits as the Horror crashed into the corner, turning directions too quickly, and quickly righted itself and charged at you. It’s flesh rolled within itself as it stomped closer, making indescribable sounds as it moved. Gaster’s hand swung up and darkness tangled with its feet, tripping it up for just a second before orange lights slashed through the air- cutting the Horror into large pieces that toppled to the ground, no blood to be seen.

Gaster slowly lowered his extended hand back to his side, paused for a moment, before turning back to you with a smile. “See? No big deal.” He knelt down in front of you again. “You do not need to be afraid of monsters when you are surrounded by them.” He said, though most of what he was saying passed right by you as you watched the grey flesh from behind him float up and start stacking on top of the other parts. 

“Hhhh… Hhhh….Haaaaahhhhhh…..” You were breathing too hard to form any words, and your legs refused to follow your commands to run. Gaster’s smile dropped when he saw your expression, and turned just in time to react to a fist slamming down to where he was a moment ago. 

You would have noted he had extraordinary reflexes, if it wasn’t for the fact that he was now pulling you this way and that, avoiding the attacks of the Horror by inches at a time. He quickly wrapped his arms around you again and once again you two teleported. 

Back into the empty room. The stomping starting up again.

You couldn’t take it. You collapsed onto the ground, sobbing into your hands. “I’m sorry, I’m sorry, I’m  _ so  _ fucking sorry…” You could feel Gaster’s eyes on you, but you continued with your apology. “I took too long making choices, I kept going safe, I kept choosing comfortable routes and I took too  _ long-  _ if I was faster- if I just went through those  _ stupid  _ ugly halls I could have had more time- time to look at the  _ fucking  _ doors and choose the right room and-  _ and- and- and- _ ”

“...Are you really going through all of that on your own?” Gaster’s quiet voice stopped your thoughts in their place. You looked up at him with your puffy face, seeing him standing with an emotion you couldn’t quite place. His eyes were trained on you, the halos seemed dull. 

“What?” You asked, only to feel the stomping getting closer. You couldn’t help but feel the terror tightening around your heart, and you let out another choked sob. Gaster sat down in front of you and placed his hands on the sides of your face again, this time his brow bones slightly lowered. 

“You have been feeling this trapped for this long?” He asked, you didn’t understand. “Do you weigh all of your choices so heavily that you think in the end, you think they will be life or death for you?” He seemed so concerned for you… but you couldn’t figure out what he was getting at. Seeing your confusion, he took a breath and tried again. He quietly said your name, softening his hold on you. “Let us start over. How did you end up here?” 

“...Here?” The stomping echoed around the room. “Someone… offered me a game. Then I was trapped- I had no choice but to run and try to get away… but I made the wrong choices and now it’s _coming for us_ because _I_ _failed-_ ” Your words were quickly running together as your panic rose, and Gaster placed a finger over your lips. 

“ _ It is rigged _ .”

The words caused time to freeze, and you stared wide-eyed at Gaster. He continued. “The game is rigged. There are no right choices, no happy endings. It is a game that is predetermined to make you suffer, before giving you dissatisfaction. You were trapped in here thinking that there was a way to survive, when there is none.” Each word felt like a punch to the gut as the helplessness set into your bones. 

“There are no happy endings…?” You repeated, voice still shaking. 

“None. The people that made the game lied about those to trick you into playing it.” He nodded, eyebrow bones lowered. “They wanted you to play for  _ their _ enjoyment, not yours. Now, is that fair?” 

You felt your breath strained as you looked down, thoughts hanging up on the no happy endings. No happy endings. No happy endings. “No… That isn’t fair at all.” You said quietly, feeling the pressure of defeat pressing all around you. 

“Then you should not play fair yourself.” 

Time became normal again, and you felt the floor shaking as the Horror was closing the distance to you two. Gaster quickly stood up and offered a hand to you. “I know you dislike using Console Commands, but I do think the game needs them this time to be playable.” 

You accepted his hand and he pulled you up, only for the Horror to appear in your view behind him in the doorway. You felt the fear tug you backwards again, but Gaster kept a tight grip on your hand, and stepped behind you, giving you a clear view of the Horror and all its grotesqueness. 

“Here. I am here to help.” Gaster motioned with his free hand, and a keyboard made of orange light appeared in front of you. The Horror stepped forward, slowly again, thinking it won once more. It just needed a few more steps and it would crush the two of you. “Go on. Show the creators what happens when they make a rigged game.” He urged you to the keyboard. 

The Horror took another step forward, and you finally reached for the keyboard and pressed the [~] key. The world shimmered before you, growing slightly brighter, and more of the texture seams became visible. Your fear was still thick in your blood as the Horror took another step closer, but you quickly typed a command onto the keyboard and raised two fingers at the Horror, pressing enter and speaking the command. 

“ **Kill** .” 

The Horror exploded into dust, turning into bright light before vanishing completely. You felt a smile on your face for the first time since the dream started. Your smile grew slightly as you looked at your hands, wondering what else you could do with the Console Commands while you were here. You quickly typed [tg] and tapped the enter button, and grass immediately grew through the tiled ground. You felt yourself giggle and you found yourself typing one string of commands after another, some that you weren’t even sure if they were real commands, but they all seemed to have an effect on the dream you were in.

You took away ceilings, then walls, then toggled the sun on. Gravity was lowered, and all enemies were removed from area- just for good measure. It was just you and Gaster, in a beautiful valley full of grass in broad daylight. You jumped and turned to face him, and he instinctively grabbed your hand to keep you from floating up too far. You used his hand to pull yourself closer to him, pulling him into a tight hug. 

“... Thank you.” You whispered, and it took a moment before Gaster embraced you back. 

“I told you I would help fend off any aliens after you tonight.” You could hear the smile in his voice. 

“I don’t think that was an alien though…”

“It sure was not based off of the alien from the movie, I could tell that much, but I will warn you that I  _ will _ be insulted if you will simply classify that being as a  _ monster _ .” Gaster lightly threatened, and you huffed part of a laugh. 

“I mean- sure, okay it was an alien. Thank you anyway, Gaster.” You smiled, not able to thank him enough for getting you out of that nightmare. “... How are you here, by the way?” You looked up at him, slowly coming to the conclusion that this was actually Gaster, not just your dream version of him.

“I have a wide range of abilities, including one that allows me to haunt the subconsciousness of others.” He said, keeping his eye halos to the horizon. “When I noticed you having a nightmare, I only meant to observe what it was about- I never intended to get involved.” 

“So why did you save me?” You asked, and you could tell he was purposely avoiding looking at you. He was silent for a moment, seeming to choose his words carefully.

“I needed to keep my word, that is all.” He settled with, letting go of the hug. You watched him as he kept his head turned away, and give him a light punch. That startled him and he looked down at you.

“Daw, you care about me.” You smiled, and he tried to mask his face with unamusement, though you could see though it. He raised a finger as if he was going to correct you again.

“Correct.” He smiled at your shock at him actually admitting it, seeming to hold back his own laugh. “Though I must admit, I did not do as much as you think I did. I just bought you time to take control of your own dream.” He looked down and brushed his foot through the lush grass. 

“What do you mean? You gave me the keyboard.” You bounced slightly, enjoying the low gravity. He watched you, amused at your lazy floating. 

“I gave you the  _ illusion _ of a keyboard. Nothing but a light show.” He held out his hands, and more orange lights danced between them. “You believed in it, and willed your actions to change your dream. Think of it as… Kickstarting lucid dreaming.” He offered simply, a rather out of character thing for him to do. 

“Huh. Well, thank you for that.” You smiled, tapping a finger on your cheek as you gently bounced on one foot. “Would you do me one more favor, since we are here?” 

He nodded, seeming to expect you wanting something more of him. “What is your request?”

“Catch me!” You cheered, leaping up into the air and gradually floating backwards. 

You heard Gaster’s breath catch and he jumped after you, expertly catching you in a bridal position mid air. After a moment, the two of you gracefully landed onto the soft grass, and you saw Gaster looking at you as you were having giggling fits. You could see him trying to mask a smile on his face as he sighed and shook his head. “So, now what?” You asked between your giggles. He considered a moment before bringing his mouth close to your ear.

“ _ I think it is time to  _ **_wake up_ ** .”

You felt your leg jerk, and your vision spun for a moment before you realized you were still in the living room. The tv was quiet, and the room had long gone cold. You noticed you were still perfectly warm however, as you felt Gaster’s arms were wrapped tightly around you, a hand placed on the back of your neck, keeping you close to his chest. His grip loosened, and he looked down at you with his bright haloed eyes. 

“No more nightmares without me, alright?” He asked. 

You nodded.

  
  
  



End file.
